There are several liquid anesthetic vaporizers or atomizing devices presently used, all of them including an anesthetic liquid storage container, having a valve containing head, a lateral inlet for the atomizing gas and an opposite outlet for the gas supported active anesthetic composition.
In known devices, the gas carrier, usually oxygen, is bifurcated in two separate streams, the first one directly leading to the said outlet, without establishing a direct contact with the anesthetic liquid, and the second one being diverted to the vaporizing chamber where its saturation occurs before being united with a further mixture with the first stream to produce the final desired concentration. The ratio of the mixture of these streams is determined by the valves.
Several disadvantages have been encountered in the use of these conventional atomizing devices, such as the following:
THE BULKY BODY OF THE STORAGE CONTAINER, USUALLY CYLINDRICAL, HAS PREVENTED OR MADE DIFFICULT THE DESIRED ASSEMBLING OF ALL THE REQUIRED PARTS, AS WELL AS THE PROVISION OF A GANG-UNIT;
ANOTHER DISADVANTAGE IN THOSE DEVICES HAVING A GAUGED OUTLET, IS GROUNDED ON THE UNDESIRED INFLUENCE OF THE VARIATION OF THE INLET FLOW OVER THE FINAL CONCENTRATION RATIO BY WHICH THE INCREASE OF THE FIRST WILL PROVOKE A DECREASING OF THE LATTER. The same influence is verified through the change of temperature, directly proportional to the increase of the said concentration, in spite of the use of bi-metal valves;
ALSO, EXTREME CARE IS REQUIRED FOR THE MOUNTING OF THE NEEDLE VALVE WHICH REGULATES THE PASSAGE OF THE SATURATED STREAM FROM THE STORAGE TANK TO THE UPPER HEAD OF THE DEVICE, IN ORDER TO ENSURE A PERFECT SHUT-OFF OF THE SAID PASSAGEWAY, AND THE OPERATING KNOB OF THE VALVE DOES NOT IMMEDIATELY INDICATE THE VALVE OPERATING STAGE;
STILL ANOTHER DRAWBACK OF CONVENTIONAL ATOMIZERS FOR ANESTHETIC LIQUID COMPOUNDS IS THAT THERE IS NO WAY TO EMPLOY EACH AND EVERY KIND OF LIQUID COMPOSITION WITH A SINGLE AVAILABLE DEVICE WHICH RESULTS IN THE UTILIZATION OF A PLURALITY OF DIFFERENT DEVICES. This problem becomes particularly acute when a full battery or set of vaporizer units are assembled in a multiple or gang-unit device, each loaded with different kinds of anesthetic compounds.
Many other serious problems are faced by anesthetists all over the world due to the lack of reliability of suitable equipment. These problems have helped to render the anesthetic profession a highly specialized one.